Method of concentrating okes



UNITED STATES PATENT OFFICE.

ROYER LUCKENBACI-I, OF BROOKLYN, NEW YORK, ASSIGNOR T0 LUCKENBACH PROCESSES, INC., OF SAN FRANCISCO, CALIFORNIA, A CORPORATION OF Patented May 23, 1922.

NEVADA.

METHOD OF CONCENTRATING ORES.

1 ,41'7,261. Specification of Letters Patent.

No Drawing.

T 0 all whom it may concern:

Be it known that I, RoYnR LUCKENBAOH, a citizen of the United States, and a resident of the borough of Brooklyn, county of Kings, city and State of New York, have invented anew and useful Method of Concentrating Ores, of which the following is a specification.

The invention relates to the concentration of "ore by flotation wherein mineral values are separated from the gangue by means of bubbles formed in a pulp comprising pulverized ore and water. The mineral values attach themselves to the bubbles and float with them to the surface and form a froth thereon, and such mineralized froth may be removed from the surface of the pulp leaving the gangue in the pulp.

The objects of the invention are to provide a rea ent for use inthe process of ore concentration which will be cheap to produce and use, which will produce a dry, and stable froth which will have a minimum attraction for gangue.

These and further objects will more fully appear in the following specification and claims.

The invention may be carried out in connection with any ores which are capable of treatment by the flotation processes at present in use.

The invention may be carried out as follows: The ore, or mill product, in a state of fine division and mixed with water to form a free flowing pulp, is agitated and aerated with the addition thereto of a colloidal solution of a gathering material and an acid,'and the concentrate is removed by froth flotation by methods usual in flotation practice. Y

The preferred gathering material for carrying out the process of the present invention is a bituminous substance such, for example, as shellac, rosin, rosin pitch, or wood tar pitch.

The rosin pitch, for example, is boiled in water in which caustic soda or sodium hydroxide has been dissolved. This will re duce the pitch to an extremely fine colloidal solution. To the colloidal solution is added a weak solution of a mild acid in water, until the mixture as a whole shows a slight acidity.

In carrying out the flotation operation the colloidal solution is added directly to the Application filed December 31, 1919. Serial No. 348,700.

ore pulp, which is agitated with the colloidal reagent and the concentration is effected by flotation of the mineral values.

The colloidal solution may be made by bollmgepproximately 1000 grams of the ros1n p1tch in a solution of 85 grams of caustic soda in 3 liters of water. After boiling for about 30 minutes the liquor is diluted with warm water to make about 15 liters and allowed to cool somewhat. To the above solution is added an 8% solution of boric acld in water. The boric acid solution is added slowly with stirring until the mixture shows a slight acidity. The amount of boric acid solution necessary will be about 550 cc.

Any of the following materials may be employed in compounding the above mixture: rosin, rosin pitch, shellac previously dissolved in alcohol, wood tar pitch, commercial resin size, or resin soap.

Any salt having an alkaline reaction may be employed in the mixture, but with a caustic alkali the action is quicker.

The colloid solution will, when mixed with the water of the pulp, form an emulsion, and the emulsified condition will be maintained.

As a practical example of the concentration of a mill product, the following results were obtained in the retreatment of tailings from the oil flotation of an ore from the Joplin, Mo, district. The assay value of the tailings was 3.9% lead.

A sample of the above described tailings weighing 169 grams was treated in a Ruth flotation machine in about 6 liters of water in which had been dissolved 1 cc. of a 40% sodium silicate solution and about 2 grams of sodium phosphate, to which 5 cc. of a rosin pitch reagent was slowly added. The machine was run for 20 minutes producing a stiff, heavy, dry, mineralized froth which was floated over the top of the machine.

The concentrates amounted to 13 grams and assayed 46.4% lead. The tailings amounted to 156 grams and assayed 0.364% lead, showing an extraction of 91.5% of the lead content of the ore used.

The rosin pitch consumption was extremely small compared to the ore, and it is safe to assume that in carrying out the process on a commercial scale a much smaller proportion of the reagent on the ore may be employed with satisfactory results.

The proportions given are approximate only, and may be varied within wide limits as depends upon the character of the ore and other conditions of operation. Some ores require a larger; or smaller amount of reagent and a longer or shorter time. These conditions can only be determined by experimenting on the ore to be concentrated.

In accordance with the provisions of the patent statutes, the principle of the invention has been described, together with what is now considered to be the best embodimentthereof, but it is to be understood that the process described is merely illustrative, and the invention may be carried out in other ways.

aving now described the invention whatis claimed and desired to be secured by Letters Patent is 1. The method of concentrating ores by flotation, which comprises aerating the ore pulp, in the presence of a mixture comprising the reaction product of a bitumen and an alkali, and a mild acid in quantity suffi cient to render the pulp non-alkaline and insufiicient to decompose the reaction product, to form a froth, and separating the froth from the pulp.

2.'The method of concentrating ores by flotation, which comprises aerating the ore pulp in the presence of a mixture comprising the reaction product of a bitumen and an alkali, and boric acid in quantity sufficient to render the pulp non-alkaline and insufficient to decompose the reaction product, to form a froth, and separating the froth from the ulp. p 3. The method of concentrating ores by flotation, which comprises aerating the ore pulp in the presence of a mixture comprising the reaction product of a bitumen and an alkali, and a mild acid in quantity sufficient to acidify the pulp and insufficient to decompose the reaction product, to form a froth, and separating the froth from the l aPThe method of concentrating ores by flotation, which comprises aerating theore pulp in the presence of a mixture comprislng the reaction product of pitch and an alkali, with a relatively mild acid in quantity sufficient to acidify the pulp and insufficient to decompose the reaction product to form a froth, and separating the froth from the pulp.

5. The method of concentrating ores by flotation, which comprises aerating the ore pulp in the presence of a mixture co1nprising the reaction product of a vegetable pitch and an alkali, with boric acid to form a froth, and separating the froth from the pulp.

6. The method of concentrating ores by flotation, which comprises aerating the ore pulp in the presence of a mixture comprising the reaction product of rosin pitch and a caustic alkali, with boric acid to form a froth, and separating the froth from the flotation, which comprises introducing into the ore pulp a mixture comprising the reaction product of rosin pitch and caustic soda, with a mild acid in quantity suflicient to render the pulp non-alkaline and insufficient to decompose the reaction product, aerating the pulp to form a froth, and separating the froth from the pulp.

9. The method of concentrating ores by flotation, which comprises introducing into the ore pulp a mixture comprising the reaction product of rosin pitch and caustic soda, with boric acid, the proportion of acid being such that the mixture will have an acid reaction, aerating the pulp to form a froth, and separating the froth from the pulp.

This specification signed and witnessed this 30th day of December, 1919.

ROYER LUCKENBACH.

Witnesses:

J. F. COLEMAN, A. E. RnNToN. 

